Biorational disease control products (fungicides, bactericides, and nematicides) fall into the same classes as the insecticides, botanicals, minerals, and synthetics. Sulfur, potassium bicarbonate, phosphites and copper compounds are examples of minerals or synthetics that can control fungal and bacterial diseases. Organic growers should be sure to check with their certifying authority for more information on these materials. Botanicals such as rosemary oil, soybean oil, or garlic extracts appear in this table and are generally approved for use in organic production. These products require thorough coverage, application at the first signs of disease, and frequent repeated dosages to be effective.
Microbial products are all living organisms that require specialized storage and application procedures. These include beneficial fungi and bacteria (Streptomyces, Gliocladium, Trichoderma harizanum) that compete with plant pathogenic fungi, produce toxic metabolites, or actively parasitize pathogens. Their effectiveness in University research trials has been inconsistent because of variations in environmental conditions and disease pressure. Microbial fungicides perform best in a greenhouse environment where they can establish and flourish. Control of plant pathogenic organisms on the phylloplane (leaf surface) is especially problematic, as the competing organisms must establish themselves and can fail due to dessication and exposure to sunlight. These materials have a limited shelf life, must be protected from temperature extremes, and correctly applied (plenty of water and under the correct environmental conditions) to be effective.
| Active Ingredient | Trade Name(s) | Target Pests | Comments |
|---|---|---|---|
| azadiractin | Aza-Direct, Azatin XL, Neemix |
Aphids, leafminers, thrips, whitefly, leafhopper, flies, true bugs, some beetles and caterpillars | Insect growth regulator, repellent, antifeedant. Disrupts growth of immature stages. Use preventatively before outbreaks. Repeat applications may be needed. Efficacy varies. |
| Beauvaria bassiana strain GHA |
Mycotrol O, BotaniGard 22WP |
Aphids, whiteflies, thrips | This fungus penetrates the insect cuticle, proliferates and eventually releases new spores. Best applied in evening. Use preventatively based on monitoring before pest populations are high. |
| Bacillus thuringiensis subsp. kurstaki |
Biobit, Deliver, Dipel, Javelin |
Caterpillars, including cranberry/cherry fruitworm, blueberry sawfly, winter moth, grape berry moth, leafrollers, etc. | Acts as stomach poison, must be ingested to be effective. Not all products are OMRI listed; check the label. |
| Bacillus thuringiensis subsp. aizawai |
Agree WG | Caterpillars, including armyworms, grapeleaf skeletonizer | Acts as stomach poison, must be ingested to be effective. OMRI listed. |
| bifenzate | Acramite 50WS, Floramite SC |
Mites | A long residual selective nerve poison for mite control. |
Burkholderia spp. strain A396 |
Venerate | Caterpillars, scale insects | Highly active against grape berry moth. Make two applications 7-days apart for each generation when needed. Grandevo and Venerate can be rotated but do not tank-mix the two products together. |
Chromobacterium subtsugae strain PRAA4-1 |
Grandevo | Grape berry moth, mites, spotted wing drosophila suppression | Early application is important for Grandevo against any of the sucking pests as the primary MOA is reduction in reproduction and typically a 7-day application interval or shorter is needed. Highly active against grape berry moth. Make 2 applications 7 days apart for each generation when needed. Grandevo WDG at 3 lb/acre + adjuvant for spotted wing drosophila. |
| extract of neem oil | Trilogy | Primarily labeled for (but not limited to) mite control | Can be used to control mites. For best results use when population levels are low to prevent build-up. Repeat applications are needed. Do use on table grapes after bloom or on wine grapes after bunch closure. |
| potassium salts of fatty acids (insecticidal soaps) | M-Pede, Des-X | Aphids, leafminers, mites, thrips, whiteflies | Works on contact. Can be phytotoxic to some crops, test on small plot first. Avoid treatment when plants are stressed or air temperatures are above 85˚F. May also harm some beneficials. Also active against powdery mildew. Do not use on table grapes onces they become 6-7 mm or use at lowest recommended rate (75 gal/A) |
| iron phosphate | Sluggo | Snails, slugs | Bait which causes feeding to cease. Death occurs over 3-5 days. Exempt from tolerance and has a zero hour reentry interval due to low mamalian toxicity. |
| methoxyfenozide | Intrepid | Many species of caterpillar | Insect Growth Regulator. Mimics molting hormone; causes premature molt and death. Labeled for Grape Berry Moth. |
| pyrethrin | Pyganic EC, Pyrenone Crop Spray |
Many pests of fruit crops; see label. | Botanical insecticide with broad-spectrum activity. Contact toxin with rapid knockdown bur short residual. Highly toxic to fish. Derived from chrysanthemum. Some formulations OMRI listed. |
| spinosad | Entrust 2SC | Caterpillars, leafminers, thrips | Acts both as a contact and stomach poison. Somewhat toxic to some beneficials. Rotate with other selective biorationals to prevent the development of resistance. |
| spiromesifen | Oberon | Whiteflies and some mites | Contact insecticide and miticide. |
| Steinernema and Heterohabditis parasitic nematode species |
Beneficial Nematodes | White grubs, weevil larvae, wireworms | Predatory nematodes seek out and penetrate host insects, multiply within the host and kill it. They are most likely to be effective against soil-dwelling immature stages of susceptible host insects. They require moist soil conditions to survive. |
| Active Ingredient | Trade Name(s) | Target Pests | Comments |
|---|---|---|---|
| Acibenzolar-S-methyl | Actigard 50 WG | Downy mildew, Xanthomonas | Plant defense activator. |
| Bacillus amyloliquefaciens | Triathlon, Double Nickel | Botrytis, Alternaria, fungal leaf spots and blights, Powdery mildew | Most recommendations are to mix Double Nickel with Cueva. |
| Bacillus pumilus strain QST 2808 | Sonata | Powdery mildew, rust, leaf spots | |
| Bacillus subtilis QST | Serenade Max | Botrytis, leaf spot, Anthracnose, Powdery mildew | |
| Calcium polysulfide | Lime-Sulfur (various manufacturers) | Cane and spur blights, Phomopsis, Fusicocum, overwintering inoculum of Monolinia | This is a caustic compound that must be thoroughly cleaned from spray equipment to avoid damage. Some formulations are OMRI listed. |
| Copper hydroxide | Champion WP, Champ, Nu-Cop, Kocide | Botrytis, Downy mildew, Powdery mildew, Anthracnose, Phomopsis | Be careful of potential phytotoxicity in some crops or cultivars; do not apply in close succession with Captan; read label carefully for cautions and restrictions. |
| Copper octanoate | Cueva | Powdery mildew, leaf spots, Anthracnose, Botrytis | |
| Copper sulfate | Cuprofix-Ultra 40 Disperss | Powdery mildew, leaf spots, Anthracnose | |
| Harpin protein | Messenger | Bacterial diseases, adverse environmental conditions | Plant defense activator; variable efficacy |
| Hydrogen dioxide | Oxidate | Alternaria, Phytophthora, Pythium, Rhizoctonia, Anthracnose, Botrytis, Powdery mildew | Kills on contact by oxidation. Will also kill beneficial organisms. Requires repeated applications. |
| Kaolin clay | Surround WP | Powdery mildew, heat stress, sunscald | Creates a thin film of clay particles on the surface of treated plants. Must be rinsed off of harvested fruit if residue persists. |
| Laminaria digitata plant extract | Vacciplant | Botrytis, Anthracnose, mummyberry | Plant defense activator. Start applications preventatively or when conditions for disease development become favorable. Reapply every 7 – 14 days. Under moderate to heavy disease pressure, tank mix this product with another registered fungicide. |
| Neem oil | Trilogy Agroneem Azatrol Aza-Direct Neemix |
Anthracnose, Botrytis, Downy and Powdery mildew | Also effective for insect and mite control. Repeat applications needed for good control. |
| Potassium bicarbonate | Kaligreen Armicarb MilStop |
Alternaria, Botrytis, Downy and Powdery mildew | |
| Potassium phosphite | ProPhyt, Phostrol | Downy mildew, Phytophthora | Systemic material |
| Mono- and dibasic sodium, potassium, and ammonium phosphites | Phostrol | Downy mildew, Pythium, Phytophthora | Systemic material, see label for tank mix cautions |
| Pseudomonas fluorescens | BlightBan A506 | Strawberry frost protection and grape bunch rot protection | For strawberry frost protection, start application when first bloom initials emerging from crown. Repeat treatments as necessary, with a total of 2-3 applications. As an aid to control bunch rot caused by species of Acetobacter bacteria (sour rot) in combination with Aspergillus niger and Botrytis cinerea. Apply at bloom and again prior to bunch closure. |
| Reynoutria sachaliensis (giant knotweed) Extract | Regalia | Botrytis, Anthracnose, mummyberry | Plant extract to boost plants’ defense mechanisms to protect against certain fungal and bacterial diseases, and to improve plant health. Applications need to start early. Regalia + NuFilm P for control of mummyberry and anthracnose fruit rot. |
| Streptomyces lydicus | Actinovate AG | Powdery mildew, Botrytis | |
| Sulfur |
Kumulus Microthiol |
Powdery mildew | Be careful of potential phytotoxicity in some crops or cultivars; do not apply in close succession with Captan; read label carefully for cautions and restrictions. |
